Pilocarpine is an alkaloid extracted from plants of the genus Pilocarpus. The drug stimulates the muscarinic receptors (especially M3, which is expressed in smooth muscles and glands) and thus induces salivation, hypertension and water intake. Pilocarpine was appoved by FDA for the alleviation of symptoms of xerostomia in patients who have undergone radiation therapy to their head and neck cancer and in patients with Sjogren's Syndrome. Ophthalmic solution of the drug is prescribed for the treatment of glaucoma, ocular hypertension, postoperative elevated intraocular pressure, etc.

Isopilocarpine is a diastereomer of pilocarpine. Isopilocarpine coexists with pilocarpine in nature and is also a degradation product of pilocarpine after oral administration to humans. It can be found in the leaves of some Pilocarpus species. Pilocarpine targets the muscarinic receptors and is approved for treatment of xerostomia. Isopilocarpine is often present in formulations of pilocarpine but has no appreciable effect on muscarinic receptors.

Pamoic acid, also called embonic acid, is a naphthoic acid derivative, used as a counter ion of a drug compound to increase the solubility of the drug in water. Pamoic acid has agonist activity for the orphan G protein-coupled receptor GPR35 by which it activates ERK and beta-arrestin2, and causes antinociceptive activity. Although (like other drug salts) it has been considered an inactive compound by the FDA.

Pilocarpine is an alkaloid extracted from plants of the genus Pilocarpus. The drug stimulates the muscarinic receptors (especially M3, which is expressed in smooth muscles and glands) and thus induces salivation, hypertension and water intake. Pilocarpine was appoved by FDA for the alleviation of symptoms of xerostomia in patients who have undergone radiation therapy to their head and neck cancer and in patients with Sjogren's Syndrome. Ophthalmic solution of the drug is prescribed for the treatment of glaucoma, ocular hypertension, postoperative elevated intraocular pressure, etc.